/Engine/Source/Editor/LandscapeEditor/Public/LandscapeToolInterface.h
bool BeginTool ( [FEditorViewportClient](API\Editor\UnrealEd\FEditorViewportClient) * ViewportClient, const [FLandscapeToolTarget](API\Editor\LandscapeEditor\FLandscapeToolTarget) & Target, const FVector & InHitLocation )